From nobody Tue Dec 16 12:38:53 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 07E4429AB0D; Fri, 9 May 2025 20:18:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746821906; cv=none; b=DIrzkQ2qbxcT3eJKuoKz/AXL+CX1Nys+HgBrSfb/reJXVYpM8CAkkhiVuI0amtPJBnxbGx9WhOjw/DwLzEyp+ONWOJFKG89845nIPmqRdKxm6Ax0XNXjASTB6jGqN7x7YZvJAWvjNn4Mib31paAUDKX8LgWQjXsFRw0xzZCSELw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746821906; c=relaxed/simple; bh=sUazod9fDHv6Y0sMdgofaAG7+zcMTxL59nufwr9DdXI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=qCyzs7YoiILcXbQIlimlkbfXP5kb8rjxxmRwVhpcZIxeTcXOelB14XzaCsQEgEWrcXbUNML4pE50D0jOhkK8mCASiN7Fhq/Xkjrt4I1rO7vCDZqCW2ToLJ9ekfFW44DQ8yXRtnr25cdTAv/CIKvCiXjYX3/54YAw5R/niRTgGf0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=q8Eb7YQJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="q8Eb7YQJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E170C4CEEE; Fri, 9 May 2025 20:18:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1746821905; bh=sUazod9fDHv6Y0sMdgofaAG7+zcMTxL59nufwr9DdXI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=q8Eb7YQJAThvBkuGKqgfPanDm3ob3CMsGx4JM1AetYfv0DYx345u4/f4DXW9LsnB5 qLfw3EezTGP/cEotZad9T0lLsamujT/OZ53mKU8PWAztmbHTNpPQXScnN0eA1Ic/J9 TuU7zS13fgSYGO45BgdglnV+rHCUaAzIw10h2j6Kdo+hExs/vvqfPoFUL/5qzTNzC3 ZYH0OhzDnckhRe0iT+ztTEq4Rm5ZmsSswzB6C4keKdC3G23B3YZBNgcHObZUS4rHIn TOeNaGV+cnTD2rSodXE/62AxaeFO0Z33oHIlY7CrjFqmEMOJPFoD5hXp9Gyt/g7Dec IuAgN7i1qVO3w== From: Josh Poimboeuf To: x86@kernel.org Cc: linux-kernel@vger.kernel.org, Petr Mladek , Miroslav Benes , Joe Lawrence , live-patching@vger.kernel.org, Song Liu , laokz , Jiri Kosina , Marcos Paulo de Souza , Weinan Liu , Fazla Mehrab , Chen Zhongjin , Puranjay Mohan Subject: [PATCH v2 58/62] livepatch/klp-build: Add stub init code for livepatch modules Date: Fri, 9 May 2025 13:17:22 -0700 Message-ID: <97663fd9f60494bf4d027114fab13540102b26fe.1746821544.git.jpoimboe@kernel.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add a module initialization stub which can be linked with binary diff objects to produce a livepatch module. Signed-off-by: Josh Poimboeuf --- scripts/livepatch/init.c | 108 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 108 insertions(+) create mode 100644 scripts/livepatch/init.c diff --git a/scripts/livepatch/init.c b/scripts/livepatch/init.c new file mode 100644 index 000000000000..2274d8f5a482 --- /dev/null +++ b/scripts/livepatch/init.c @@ -0,0 +1,108 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Init code for a livepatch kernel module + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include + +extern struct klp_object_ext __start_klp_objects[]; +extern struct klp_object_ext __stop_klp_objects[]; + +static struct klp_patch *patch; + +static int __init livepatch_mod_init(void) +{ + struct klp_object *objs; + unsigned int nr_objs; + int ret; + + nr_objs =3D __stop_klp_objects - __start_klp_objects; + + if (!nr_objs) { + pr_err("nothing to patch!\n"); + ret =3D -EINVAL; + goto err; + } + + patch =3D kzalloc(sizeof(*patch), GFP_KERNEL); + if (!patch) { + ret =3D -ENOMEM; + goto err; + } + + objs =3D kzalloc(sizeof(struct klp_object) * (nr_objs + 1), GFP_KERNEL); + if (!objs) { + ret =3D -ENOMEM; + goto err_free_patch; + } + + for (int i =3D 0; i < nr_objs; i++) { + struct klp_object_ext *obj_ext =3D __start_klp_objects + i; + struct klp_func_ext *funcs_ext =3D obj_ext->funcs; + unsigned int nr_funcs =3D obj_ext->nr_funcs; + struct klp_func *funcs =3D objs[i].funcs; + struct klp_object *obj =3D objs + i; + + funcs =3D kzalloc(sizeof(struct klp_func) * (nr_funcs + 1), GFP_KERNEL); + if (!funcs) { + ret =3D -ENOMEM; + for (int j =3D 0; j < i; j++) + kfree(objs[i].funcs); + goto err_free_objs; + } + + for (int j =3D 0; j < nr_funcs; j++) { + funcs[j].old_name =3D funcs_ext[j].old_name; + funcs[j].new_func =3D funcs_ext[j].new_func; + funcs[j].old_sympos =3D funcs_ext[j].sympos; + } + + obj->name =3D obj_ext->name; + obj->funcs =3D funcs; + + memcpy(&obj->callbacks, &obj_ext->callbacks, sizeof(struct klp_callbacks= )); + } + + patch->mod =3D THIS_MODULE; + patch->objs =3D objs; + + /* TODO patch->states */ + +#ifdef KLP_NO_REPLACE + patch->replace =3D false; +#else + patch->replace =3D true; +#endif + + return klp_enable_patch(patch); + +err_free_objs: + kfree(objs); +err_free_patch: + kfree(patch); +err: + return ret; +} + +static void __exit livepatch_mod_exit(void) +{ + unsigned int nr_objs; + + nr_objs =3D __stop_klp_objects - __start_klp_objects; + + for (int i =3D 0; i < nr_objs; i++) + kfree(patch->objs[i].funcs); + + kfree(patch->objs); + kfree(patch); +} + +module_init(livepatch_mod_init); +module_exit(livepatch_mod_exit); +MODULE_LICENSE("GPL"); +MODULE_INFO(livepatch, "Y"); +MODULE_DESCRIPTION("Livepatch module"); --=20 2.49.0